Using a FLIR for Bowhunting

By Pat Lefemine, Founder
Bowsite.com

Owning Bowsite.com comes with some great perks. In addition to opportunities
for great hunts, the next best thing is evaluating hunting
gear.

If you haven't heard about FLIR yet, wait – you will. A FLIR device uses space-age
technology to visualize heat differentials between objects. Most likely you've seen
them on military combat videos and police TV shows. Until recently, FLIR
technology has been prohibitively expensive and used almost exclusively by military,
fire departments, police, and specialized applications. But there is a new
market that FLIR is interested in pursuing and that's hunting.

We spoke to FLIR and arranged a loaner unit for the
2012/2013 hunting season. FLIR is relatively new to the hunting market so we
were honored when they asked us to try the unit in the field and evaluate its
usefulness. We jumped at the chance.

The unit provided to us was a FLIR TS32 PRO

FLIR is advanced technology and I'm sure some of you (who
feel hunting already has enough technology) may react negatively to using it in
the field. We can respect that. Also, for the record, FLIR is not a Bowsite.com
sponsor. They asked us to review a unit and give it an honest
review. The first question I had was if there is a fit for hunters? The
second question was how well would it perform under a variety of hunting scenarios conditions? Finally, was it truly useful? In time, that question would be
answered.

FLIR Hunting Applications

The first conversation with FLIR centered on the types of
applications hunters could use these units for. I imagined the scenarios were limited.
My main goal was to conduct scouting surveys at night. I was also interested in
using it for night predator hunts (where it's legal). While talking to FLIR
we learned there were other relevant applications as well. Here are the main
ones:

Scouting fields both night and day

Finding wounded or downed game

Predator hunting

Identifying the thermal efficiency of winter clothing

Glassing

There are other applications which have nothing to do with
hunting but are 'value-add' benefits. Such as checking the thermal efficiency
of your home for heat loss, looking for leaky pipes, finding studs, and marking
rocks in fields. For the purpose of this review we'll just stick with the
hunting related items above. Let's take them one at a time.

Note: It is recommended that you check your state game
laws regarding use and restrictions of thermal imagers. If laws do not exist,
or they are ambiguous, contact a DNR official before you use it for hunting.

Scouting
Fields (Night and Day)

The ability to rapidly scan fields (without
spotlighting) is a major benefit to thermal imaging. It was the only
application I envisioned before I talked with FLIR. Many states do not allow
casting a visible light into fields - but thermal imaging does not
illuminate anything. It reads the heat signature of objects relative to the
surroundings. The day we received our unit my son and I drove around checking fields. A doe had crossed in front of the truck and
ran into an open meadow. At 10 PM it vanished as soon as she cleared the
headlights. My son pulled up the FLIR and freaked out. The doe was running
with a 20" wide buck in velvet so the heat signature from his August
horns showed up clearly on the FLIR. My son took a video and a photo of the scene.

The deer at the top of this field is a nice 8 I had been watching for two years. we shot this photo from the road at 10 pm in November. knowing the fields he frequented after dark was valuable information. In this FLIR image he is 350 yards away and our unit was set to 'black hot' mode.

We drove by several fields that
evening and identified dozens of deer and coyotes. The FLIR worked great
for open fields, but it was just as effective finding deer in timber. This was
an unexpected surprise. We found as many deer in the trees as we
did in the open. One observation: the deer in the trees must feel invisible
at night. They would stand motionless from distances as close as 20 yards.

This image was taken while driving by a patch of timber. The deer is 100 yards into the trees and clearly visible. the amount of deer we found feeding inside timber was just about equal to the number we counted in the field. This FLIR image was captured using Instalert level 1.

We learned which fields the deer
liked, which ones they did not, and even identified a few bucks during the
antler growing summer months. The unit will identify horns in velvet, but later learned that hard horns were tough to identify.

During the post season of 2013,
we stepped up our scouting as we do every winter. My son and I expected the
thermal signature of deer and predators to jump out due to the bitter cold
weather. What we found was the opposite. Deer and Coyotes were harder to identify.
At first we were puzzled, but soon realized that their winter coat was so efficiently retaining heat that it was more difficult to detect with the FLIR. We could still spot them close, but longer
distances were a challenge.

Finding
wounded or downed game (day or night)

If you hunt long enough you are
bound to have a poor hit and a difficult recovery. I've been on plenty of
trails where the blood sign ran out and I just knew the deer was lying within
a couple hundred yards. Just last year my buddy shot a great buck in
Kansas and lost it. We frantically searched the open prairie - checking every
plumb thicket and brush pile for hours. I envisioned a FLIR would be helpful
in a recovery scenario. I had no idea just how useful it would be until testing it.

During opening week of archery
season, my son Matt and I headed to one of our favorite spots. A doe showed up
before legal sunset and he delivered a great arrow. The fatally shot doe ran
out of sight. He was anxious to try the FLIR so after the appropriate
wait time we headed back to the truck, grabbed the unit, and walked back to the
stand. It took my son less than 3 seconds to spot the dead deer. It was lying in thickets a hundred yards away. I had to see it to believe it. The deer was glowing red
in the viewfinder. There was zero chance of seeing this deer from the stand
since it had fallen into a clump of laurels. To describe the capabilities as
"impressive" was an understatement. The application for game recovery is by
far the strongest justification for owning a unit in our opinion.

This is a deer I shot in December and filmed by my son Matt. The first photo was taken from my treestand 30 minutes before last light at a distance of roughly 150 yards. We could only see the deer with the FLIR. The 2nd photo was taken 40 yards away in total darkness. Just like the first photo, we could not identify the deer with our flashlights but it was cleary visible with our FLIR.

However, it didn't do a great job
of finding a blood trail. Since Matt's deer was shot when it was 60 degrees we
assumed the warm temperature may be a factor. So we tried it again on blood
trails in November and December and achieved the same result. It seems that
drops and spatter cool down quickly and the FLIR provided little assistance for
spotting blood. Pools were a different story. They stood out better within 30
minutes of the shot. Unless you get down immediately (and we all know that's
not smart) I wouldn't bother looking for blood with a thermal unit. Its best use is
locating the animal itself.

We used the unit on four recoveries
in 2012. It performed extremely well on three of them. It did not do well on
one particular recovery. I had made a poor shot on a nice buck. The liver hit deer ran to an area thick with fallen
trees and brush piles. It was late afternoon and everything was glowing in the FLIR's viewfinder. We
knew the deer was bedded somewhere in that tangle but there was not enough temperature
differential to pick it out. I was a bit disappointed. This was the first
recovery where I needed assistance from the unit (the other three hits
were slam dunks). We got the deer, but the FLIR played no role in that recovery.

Comparison video on a deer kill : Normal Video vs. FLIR

Predator
Hunting

Once deer season was over we hung up the bows and picked up
our AR-15 rifles to annihilate as many coyotes as we could find. Some states
allow night hunting and we were looking forward to putting the FLIR to good use
on those hunts. The results were mixed. Mostly due to the lens version we had
requested. FLIR makes both a wide angle unit and one with a telephoto lens.
We opted for the wide angle camera since it was better suited for recovering
animals. For deer sized game, positive identification was made every time
within 100 yards. For coyotes, it was far, less - about 50 yards. You would see
stuff moving around at greater distances but it was hard to positively identify
it. But it was still useful. On one hunt my buddy shot a song dog at 350
yards across a sage flat. We searched for 30 minutes and couldn't find it. My son Matt
pulled out the FLIR and spotted the dead coyote within 1 minute. For
Predator hunts I would suggest FLIR's telephoto model. We found gun hunting
applications needing magnification ran 10-1 over applications better suited to the
wide-angle model.

Identifying
the thermal efficiency of your hunting clothing

When it comes to
efficiently staying warm (and dry) I am an absolute nut about my hunting outerwear.
How well the clothing insulates and traps your body heat is critical for
hunters. Now that I had a FLIR I was able to compare outfits and perform real-world
tests on popular hunting systems. What we found was amazing. There were stark
differences between outerwear brands. I don't know that this alone is a compelling
reason to invest in FLIR technology but it was certainly helpful to us in our
tests.

Glassing

So this one gets a bit tricky. And I personally never tested it during a hunt. A magnified FLIR could greatly improve your ability to find both mobile
and bedded game animals. Like many of you, I've spent countless hours glassing
for mule deer, goats, sheep, moose, and other game animals where glassing and
spotting is a necessity. Imagine being able to check a distant sage slope for deer
without relying on an ear flick, or a glowing tine? Given the right
conditions, the animal could conceivably jump right out in a FLIR. But it won't
always be the case and we proved this several times during our deer hunts back
home. Animals laying in the sun are extremely hard to differentiate with their
surroundings. A muley laying in the shade of a big rock will likely not be noticeable
on warm, clear days. The sunny rock will be, but the deer will be cooler (remember, the unit sees temperature differentials and sometimes the heat
signature of surrounding objects will be greater). If it's a cold, overcast day
it would work better. Now I personally have to draw the line on this and
believe it presents an unfair advantage to the hunter. My prediction is that as thermal cameras gain in popularity, a series of game law restricting their use while
pursuing animals would soon follow.

Using the FLIR

Using the unit is quite simple to operate and can be
mastered in five minutes.

The device we evaluated is basically a monocular. FLIR does license
their technology for rifle scopes along with other applications but we wanted
something versatile. The device we tested was easy to operate with very basic
functions. After hitting power (and enduring a short boot-up period) you simply
point the unit in the direction you wish to search. That's it.

You can choose the way you'd like the device to show you the
image. There are several common display modes including the typical "White
Hot" mode where the items with strong heat signatures glow white amidst a dark
background. The inverse of this is "Black Hot" where the surroundings are
light and the heated object is black. Our favorite is "Instalert
1" which displays the heated object in red amidst a black and white
environment. There were several Instalert intensity settings but we rarely
used anything more than levels 1 or 2. This is the fastest way to identify
objects that have significant heat differential compared with their
surroundings and was useful for our test applications.

Here are two deer feeding 20 yards beneath us 30 minutes before it was light enough to see. We took three photos of them to demonstrate the variety of display modes on our FLIR.

There is a button for digital zoom which digitally magnifies
the image by 2x. There are higher magnification lens kits available for our FLIR
but we didn't have one to test.
I would like to test units with the higher magnification in the future.

The final button is for taking photos and video clips. This
unit captures media to an SDHD card so we are able to take both video, and
snapshots of anything we saw in the viewfinder. The resolution of the images
was degraded more than what we saw on screen. This made our photo and video
captures appear overly pixilated. It looked much better while using the unit.

The unit is powered by 8 AA rechargeable NiMH 2700
batteries. You can use Lithium batteries but they are expensive and the unit
consumes them quickly. The unit won't work with standard AA batteries. For
scouting I strongly recommend a car charging accessory so you are not killing
your batteries while driving around. In the field, you have to manage your battery
life with prudence. I was disappointed with the battery efficiency of this
particular unit.

Finally, the unit is water resistant and enclosed in a
rugged case. We didn't test how water resistant it is since taking a chance of ruining
the unit was probably not a good idea. According to FLIR our unit can withstand
a dunking.

Positives

There were many positive aspects to using the FLIR while
hunting. The ability to see in total darkness, the ability to spot game at distances
(up to 300 yards with the wide angle version) and the ability to detect and
find downed or wounded game in mere seconds. The unit has some additional
features such as evaluating thermal properties of clothing and structures but
those are probably not compelling reasons for a purchase.

The unit is very simple to use. A 5 year old can do it. It
is lightweight, rugged, waterproof, and somewhat ergonomically designed. FLIR
makes a different unit (PS) that is smaller and better suited for hunting
but it lacked the recording feature. When given the choice, we opted for the
larger (TS PRO) unit. The ability to capture the scene to media is a plus.

Negatives

There's one big negative; the price. The FLIR unit we tested
has a list price around $6,000.00. They have a smaller unit with a bit less
resolution and no media capture for around $2,000. Considering similar units
were $25,000 just a few years ago it appears the price is moving in the right
direction. Still, it's hard for the average hunter to justify a FLIR purchase.
Like any new technology, the price may decrease in time and become a better
value proposition for hunters. We had fun using ours and I'm going to have a
hard time sending it back. For predator and hog hunters the scope version is very
pricey but it would be incredible for hunting hogs and predators at night. On
my particular unit I was very disappointed in the battery life. It had to be
managed at all times. The resolution of the unit was acceptable, but not
great. There are better units by FLIR but they are restricted for Government
use and priced far beyond the hunting market.

Summary

I have no doubt that FLIR devices will find their way into a
small segment of the hunting population. They are incredibly useful for
scouting - both day and night. The application for game recovery is outstanding-
almost scary. And they are simply a lot of fun to use. The current price is
a significant limiter for widespread adoption. Without a considerable price
decrease individual hunters will have a tough time justifying the purchase.
But I can see a hunting club buying a unit for game recovery, surveys / deer
counts, or for varmint eradication. If I had it to do over again I'd opt for
a higher magnification unit. The wide angle was good for recoveries and short
distance use, but for scouting, predator hunting, and even game recovery FLIR's
65mm unit would have been much better. The perfect solution would be a unit
with a zoom lens, replaceable batteries, and a price point of $1000. Given the
components required to enable Thermal Imaging, I don't see my dream unit
hitting the shelves anytime soon. But if any company can do it, FLIR can. It
just may take a while longer.